Remove the screw on the plastic cover. Increase the pressure to the "+" indicator to fine-tune, and to lower the pressure to the indicator to fine-tune. Type: pressure 1-1.8kg/cm² 1/4" outer wire / pressure 1-1.8kg/cm² 1/4" inner wire / pressure 1-1.8kg/cm² 3/8" inner wire / pressure 1.5-2.2kg/cm² 1/4" outer wire / pressure 1.5-2.2kg/cm² 1/4" inner Wire/ pressure 1.5-2.2kg/cm² 3/8" inner wire.
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